1. Field of the Invention
The invention concerns a magnetic resonance apparatus with a scanner having a superconducting basic field magnet, a gradient coil unit and a radio-frequency antenna unit, an electronics unit and a cooling apparatus, wherein the cooling apparatus has a cryostat for cooling the superconducting basic field magnet and a cooling circuit for cooling the electronics unit and/or the gradient coil unit and/or the radio-frequency antenna unit.
2. Description of the Prior Art
Superconducting magnets in magnetic resonance apparatuses are permanently cooled with liquid helium even in a non-operating state of the magnetic resonance apparatus, in order to prevent an unwanted boil-off of helium. In order to cool the liquid helium and the magnet, the magnetic resonance apparatus has a cryostat. Such cryostats usually have a so-called cold head, which generates an operating coldness level of the magnet. Waste heat of approx. 5 KW, which must be discharged by a cooling apparatus, is produced at the cold head. This cooling apparatus must function very reliably in order to prevent the unwanted boil-off of helium.